[PATCH 02/10] block: convert blk-mq hw sysfs show to sysfs_emit/sysfs_emit_at

[Jackie Liu <liu.yun@linux.dev>]

From: Jackie Liu <liuyun01@kylinos.cn>

Use sysfs_emit() for nr_tags and nr_reserved_tags, and convert
cpus_show to use sysfs_emit_at() which also drops the manual
PAGE_SIZE tracking.

Signed-off-by: Jackie Liu <liuyun01@kylinos.cn>
---
 block/blk-mq-sysfs.c | 19 ++++++++++---------
 1 file changed, 10 insertions(+), 9 deletions(-)

diff --git a/block/blk-mq-sysfs.c b/block/blk-mq-sysfs.c
index 58ec293373c6..ed9546de7466 100644
--- a/block/blk-mq-sysfs.c
+++ b/block/blk-mq-sysfs.c
@@ -69,36 +69,37 @@ static ssize_t blk_mq_hw_sysfs_show(struct kobject *kobj,
 static ssize_t blk_mq_hw_sysfs_nr_tags_show(struct blk_mq_hw_ctx *hctx,
 					    char *page)
 {
-	return sprintf(page, "%u\n", hctx->tags->nr_tags);
+	return sysfs_emit(page, "%u\n", hctx->tags->nr_tags);
 }
 
 static ssize_t blk_mq_hw_sysfs_nr_reserved_tags_show(struct blk_mq_hw_ctx *hctx,
 						     char *page)
 {
-	return sprintf(page, "%u\n", hctx->tags->nr_reserved_tags);
+	return sysfs_emit(page, "%u\n", hctx->tags->nr_reserved_tags);
 }
 
 static ssize_t blk_mq_hw_sysfs_cpus_show(struct blk_mq_hw_ctx *hctx, char *page)
 {
-	const size_t size = PAGE_SIZE - 1;
 	unsigned int i, first = 1;
-	int ret = 0, pos = 0;
+	int ret, pos = 0;
 
 	for_each_cpu(i, hctx->cpumask) {
 		if (first)
-			ret = snprintf(pos + page, size - pos, "%u", i);
+			ret = sysfs_emit_at(page, pos, "%u", i);
 		else
-			ret = snprintf(pos + page, size - pos, ", %u", i);
+			ret = sysfs_emit_at(page, pos, ", %u", i);
 
-		if (ret >= size - pos)
+		if (ret <= 0)
 			break;
 
 		first = 0;
 		pos += ret;
 	}
 
-	ret = snprintf(pos + page, size + 1 - pos, "\n");
-	return pos + ret;
+	ret = sysfs_emit_at(page, pos, "\n");
+	if (ret > 0)
+		pos += ret;
+	return pos;
 }
 
 static struct blk_mq_hw_ctx_sysfs_entry blk_mq_hw_sysfs_nr_tags = {
-- 
2.51.1